8A9Z

Tubulin-[1,2]oxazoloisoindole-2e complex


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.29 Å
  • R-Value Free: 0.240 
  • R-Value Work: 0.199 
  • R-Value Observed: 0.210 

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Ligand Structure Quality Assessment 


This is version 1.1 of the entry. See complete history


Literature

Development of [1,2]oxazoloisoindoles tubulin polymerization inhibitors: Further chemical modifications and potential therapeutic effects against lymphomas.

Barreca, M.Spano, V.Rocca, R.Bivacqua, R.Abel, A.C.Maruca, A.Montalbano, A.Raimondi, M.V.Tarantelli, C.Gaudio, E.Cascione, L.Rinaldi, A.Bai, R.Steinmetz, M.O.Prota, A.E.Alcaro, S.Hamel, E.Bertoni, F.Barraja, P.

(2022) Eur J Med Chem 243: 114744-114744

  • DOI: https://doi.org/10.1016/j.ejmech.2022.114744
  • Primary Citation of Related Structures:  
    8A9T, 8A9Z

  • PubMed Abstract: 

    Lymphomas are among the ten most common cancers, and, although progress has been achieved in increasing survival, there is still an unmet need for more effective therapeutic approaches, including better options for patients with refractory tumors that initially respond but then relapse. The lack of effective alternative treatment options highlights the need to develop new therapeutic strategies capable of improving survival prospects for lymphoma patients. Herein, we describe the identification and exploration of the SAR of a series of [1,2]oxazolo[5,4-e]isoindoles as potent small molecules that bind to the colchicine site of tubulin and that have promise for the treatment of refractory lymphomas. Exploration of the chemical space of this class of compounds at the pyrrole moiety and at the [1,2]oxazole ring highlighted two compounds bearing a 3,5-dimethoxybenzyl and a 3,4,5-trimethoxybenzyl group as potent candidates and showed that structural modifications at the isoxazole moiety are generally not favorable for activity. The two best candidates showed efficacy against different lymphoma histotypes and displayed 88 and 80% inhibition of colchicine binding fitting well into the colchicine pocket, as demonstrated by X-ray crystallography T 2 R-TTL-complexes, docking and thermodynamic analysis of the tubulin-colchicine complex structure. These results were confirmed by transcriptome data, thus indicating [1,2]oxazolo[5,4-e]isoindoles are promising candidates as antitubulin agents for the treatment of refractory lymphomas.


  • Organizational Affiliation

    Department of Biological, Chemical and Pharmaceutical Sciences and Technologies (STEBICEF), University of Palermo, Via Archirafi 32, 90123, Palermo, Italy.


Macromolecules
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Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Tubulin alpha-1B chain
A, C
451Bos taurusMutation(s): 0 
UniProt
Find proteins for P81947 (Bos taurus)
Explore P81947 
Go to UniProtKB:  P81947
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP81947
Sequence Annotations
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  • Reference Sequence
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Entity ID: 2
MoleculeChains Sequence LengthOrganismDetailsImage
Tubulin beta-2B chain
B, D
445Bos taurusMutation(s): 0 
UniProt
Find proteins for Q6B856 (Bos taurus)
Explore Q6B856 
Go to UniProtKB:  Q6B856
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UniProt GroupQ6B856
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  • Reference Sequence
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Entity ID: 3
MoleculeChains Sequence LengthOrganismDetailsImage
Stathmin-4143Rattus norvegicusMutation(s): 0 
Gene Names: Stmn4
UniProt
Find proteins for P63043 (Rattus norvegicus)
Explore P63043 
Go to UniProtKB:  P63043
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UniProt GroupP63043
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  • Reference Sequence
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Entity ID: 4
MoleculeChains Sequence LengthOrganismDetailsImage
Tubulin beta-2B chain384Gallus gallusMutation(s): 0 
Gene Names: TTL
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  • Reference Sequence
Small Molecules
Ligands 7 Unique
IDChains Name / Formula / InChI Key2D Diagram3D Interactions
GTP
Query on GTP

Download Ideal Coordinates CCD File 
G [auth A],
O [auth C]
GUANOSINE-5'-TRIPHOSPHATE
C10 H16 N5 O14 P3
XKMLYUALXHKNFT-UUOKFMHZSA-N
ACP
Query on ACP

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W [auth F]PHOSPHOMETHYLPHOSPHONIC ACID ADENYLATE ESTER
C11 H18 N5 O12 P3
UFZTZBNSLXELAL-IOSLPCCCSA-N
GDP
Query on GDP

Download Ideal Coordinates CCD File 
J [auth B],
S [auth D]
GUANOSINE-5'-DIPHOSPHATE
C10 H15 N5 O11 P2
QGWNDRXFNXRZMB-UUOKFMHZSA-N
LO9 (Subject of Investigation/LOI)
Query on LO9

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N [auth B],
U [auth D]
7-[(3,5-dimethoxyphenyl)methyl]pyrrolo[3,4-g][1,2]benzoxazole
C18 H16 N2 O3
GVTUEXALHVXNOH-UHFFFAOYSA-N
MES
Query on MES

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M [auth B]2-(N-MORPHOLINO)-ETHANESULFONIC ACID
C6 H13 N O4 S
SXGZJKUKBWWHRA-UHFFFAOYSA-N
CA
Query on CA

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I [auth A],
L [auth B],
Q [auth C],
R [auth C],
V [auth E]
CALCIUM ION
Ca
BHPQYMZQTOCNFJ-UHFFFAOYSA-N
MG
Query on MG

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H [auth A],
K [auth B],
P [auth C],
T [auth D]
MAGNESIUM ION
Mg
JLVVSXFLKOJNIY-UHFFFAOYSA-N
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.29 Å
  • R-Value Free: 0.240 
  • R-Value Work: 0.199 
  • R-Value Observed: 0.210 
  • Space Group: P 21 21 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 104.5α = 90
b = 155.847β = 90
c = 178.855γ = 90
Software Package:
Software NamePurpose
PHENIXrefinement
XDSdata scaling
PDB_EXTRACTdata extraction
XDSdata reduction
PHENIXphasing

Structure Validation

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Ligand Structure Quality Assessment 


Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
Ministero dell Universita e della RicercaItalyMIUR
National Institutes of Health/National Cancer Institute (NIH/NCI)United StatesHHSN261200800001E
European CommissionEuropean Union860070 TubInTrain
Swiss National Science FoundationSwitzerland31003A_166608

Revision History  (Full details and data files)

  • Version 1.0: 2022-11-09
    Type: Initial release
  • Version 1.1: 2024-01-31
    Changes: Data collection, Refinement description